Replacement piston Unit Fits Max CN55 (CN55A2-19). This is a generic replacement driver with o-ring for the Max CN55 coil nail guns. This comes with a patent pending locking mechanism which will not allow the driver to unscrew from the piston. Aluminum is crimped into the unilok grooves of the shaft to prevent unscrewing. Guaranteed never to unscrew.
- Heat treated tool steel 6150 - Rockwell hardness 50-52
- Aerospace grade #2024 Aluminum piston
- Mechanically locked piston driver interface